1. Field of the Invention
This invention relates to a method for forming durable creases in a cellulosic fiber textile. By the term "creasing" or "crease formation" used herein it is meant that fabric generally having a flat surface is given a surface change in the form of creases or wrinkles consisting of ridges and furrows. The term is used to encompass pleating.
2. Prior Art
A number of methods are known for creasing cellulosic fiber textiles. For example, JP-B 5867/1981 and 39548/1984 propose a creasing method using a special creasing machine. Undesirably, the thus formed creases are temporary and less durable to washing.
Also known is a method of impregnating a cellulosic fiber textile with a cellulose-reactive resin, creasing the impregnated textile by means of a creasing machine and heat treating the textile for setting creases or pleating the impregnated textile and heating it for setting pleats. This method has the drawbacks that formaldehyde is often left in the textile and the resultant creases or pleats are reduced in strength and less durable to washing.
One known method for improving the durability to washing of creases is by charging a boiling or scouring kier with creased cellulosic fiber textiles to a volume of about 10% of the entire volume, placing fabric pieces thereon, and effecting scouring in a conventional manner. However, the thus treated creases are still less durable to washing and the textile becomes harder in hand and feel.